Some downhole tools are actuated by a ball, or other form of plug included herein under the term “ball”, which is intended to be useful to create a hydraulic pressure of actuation. Examples of various downhole tools requiring launched ball actuation are tools with sliding sleeve valves, liner hangers, etc.
In use, a ball may be released to travel through the well's tubular string to land in a valve seat in the string inner bore in order to create a pressure differential to operate the tool hydraulically. Generally, such a ball is launched from surface. However, in some instances, for example, when unable to pump the ball or to release the ball through the running string, it may be useful to launch a ball from a downhole location.